Sub-gauge shotgun hull

ABSTRACT

The present invention provides for a shotgun shell hull for a shotgun of a greater gauge that can be loaded with the standard load of a lesser gauge. In one embodiment, the shotgun shell hull is comprised of (i) a tubular casing having an outer diameter of about a greater gauge and an inside diameter of about a lesser gauge; (ii) a primer receiver located on a first end of the tubular casing, configured to receive a primer and having a rim for retaining the tubular casing within a firing chamber of a shotgun of the greater gauge; and (iii) a closure located on a second end of the tubular casing distal to the first end and configured to retain a charge for the lesser gauge in the tubular casing until the primer is ignited.

TECHNICAL FIELD OF THE INVENTION

[0001] The present invention is directed, in general, to a shotgun shell hull and, more specifically, to a shotgun shell hull having external measurements of one gauge and internal measurements of a smaller gauge.

BACKGROUND OF THE INVENTION

[0002] Most shotgun shooters, particularly competitive shooters, want to shoot the same shotgun for all purposes. This is because shooting a shotgun is largely a matter of feel and familiarity with a particular shotgun greatly enhances scores. Because most shooting events limit the gauge of shotgun that can be used in that event and because most shooters will shoot in a number of events, a shooter either must use more than one gun or rely on some other means to compete within the stated rules. In order to keep the same “feel” in his or her gun, as well as to reduce shooter's investment in shotguns, most shooters rely on multiple barrel sets (one receiver with barrels of different gauges fitted thereto), or tubed sets (sub-gauge tubes that are inserted in the barrels of the gun). Both of these options are still costly as tubes are generally custom manufactured to a specific gun and the cost of extra barrels can easily equal one-half the cost of the gun itself.

[0003] Some additional options have developed over time that are somewhat less expensive. Some companies, for example, have started to manufacture tubes that do not need fitting and others have started to manufacture small tubes that are only partially inserted in the shotgun barrel. A more recent development has been the use of small tubes designed to be inserted in the chamber of the shotgun and are only long enough to receive the sub-gauge shotgun shell. Notwithstanding these developments, a shooter must have the devices before he or she can use them.

[0004] An easier and quicker solution to the sub-gauge problem would be to have shotgun shells of a smaller gauge that can be fired in a larger gauge shotgun. This would allow competition shooters to easily switch between different gauges. Even more significant would be the versatility offered to the casual shooter with a single shotgun who could now use sub-gauge loads in his or her shotgun. Thus an older shooter who does not want to bear the punishment of a larger bore load could use the same shotgun but with a smaller gauge load. Consider the shooter who has a single gun and wants to teach his or her child how to shoot, but does not want to scare or punish the child with excessive recoil and does not have one of the various devices that permits the use of sub-gauge loads in the gun.

[0005] Accordingly, what is needed in the art is a sub-gauge shotgun shell that can be safely shot from a larger gauge shotgun.

SUMMARY OF THE INVENTION

[0006] To address the above-discussed deficiencies of the prior art, the present invention provides for a shotgun shell hull for a shotgun of a greater gauge that can be loaded with the standard load of a lesser gauge. In one embodiment, the shotgun shell hull is comprised of (i) a tubular casing having an outer diameter of about a greater gauge and an inside diameter of about a lesser gauge; (ii) a primer receiver located on a first end of the tubular casing, configured to receive a primer and having a rim for retaining the tubular casing within a firing chamber of a shotgun of the greater gauge; and (iii) a closure located on a second end of the tubular casing distal to the first end and configured to retain a charge for the lesser gauge in the tubular casing until the primer is ignited.

[0007] The present invention thus provides a shotgun shell of a smaller gauge that can be fired in a shotgun of a larger gauge. Thus, a clay target shooter or sportsman hunter can increase the versatility of his or her shotgun without having to purchase expensive sub-gauge tubes or adding other mechanical devices to the gun.

[0008] In one embodiment of the invention to be illustrated and described, the shotgun shell hull uses a crimp formed from the outer diameter of the tubular casing as a closure to hold the lesser gauge shotgun shell charge in the hull. In still another embodiment the closure is a crimp formed from the inside diameter of the tubular casing. In yet another embodiment of the invention the closure used to retain the sub-gauge charge in the hull is an overshot wad. As those skilled in the pertinent art will understand, any type of closure can be used to retain the sub-gauge charge in the hull and still be within the scope of the present invention.

[0009] One embodiment of the invention provides for the shotgun shell hull to utilize a plastic tubular casing. In another embodiment the tubular casing is paper. Of course, any other material, such as brass or other metallic material can be used for the tubular casing and still be within the intended scope of the present invention.

[0010] Another embodiment of the present invention provides for the greater gauge of the shotgun shell hull outer diameter to be selected from the group consisting of a ten gauge; a twelve gauge; a sixteen gauge; a twenty gauge; and a twenty eight gauge. In yet still another embodiment of the invention the lesser gauge of the inside diameter of the shotgun shell hull is selected from the group consisting of a twelve gauge; a sixteen gauge; a twenty gauge; a twenty eight gauge, and a 410 gauge.

[0011] The foregoing has outlined preferred and alternative features of the present invention so that those skilled in the art may better understand the detailed description of the invention that follows. Additional features of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiment as a basis for designing or modifying other structures for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] For a more complete understanding of the present invention, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which: FIG. 1 illustrates a cut away isometric view of a shotgun shell hull constructed in accordance with the present invention;

[0013]FIG. 2 illustrates a breakout view of the charge components loaded in a shotgun shell hull of the type illustrated in FIG. 1; and

[0014]FIG. 3 illustrates isometric views of embodiments of the present invention showing various closure arrangements for forming a closure at the second end of the shot shell hull illustrated in FIG. 1.

DETAILED DESCRIPTION

[0015] Referring initially to FIG. 1, illustrated is a cut away isometric view of a shotgun shell hull 100 constructed in accordance with the present invention. The hull 100 is shown as if loaded, but with the powder, wad and shot components omitted for explanatory purposes. The hull 100 has a tubular casing 110 that has an outer diameter 120 designed to be utilized in a shotgun of a predetermined bore diameter or gauge. For example, if the hull 100 is intended for use in a twelve gauge shotgun, the outside diameter 120 will be the same approximate size as the outside diameter 120 of a standard twelve gauge shotgun shell so the hull 100 can to be chambered in a standard twelve gauge shotgun. The inside diameter 130 of the tubular casing 110 is the same approximate size as the inside diameter 130 of a shotgun shell of a lesser gauge. Thus, in one embodiment of the invention, the outside diameter 120 of the tubular casing 110 will be about the same as the outside diameter 120 of a twelve gauge shotgun shell and the inside diameter 130 will be about the same diameter as the inside diameter 130 of a twenty gauge shotgun shell. Of course, those skilled in the pertinent art will understand that the outside diameter 120 can be the same as the outside diameter of any gauge of shotgun shell and the inside diameter 130 can be the same as the inside diameter of any lesser gauge of shotgun shell and be well within the intended scope of the present invention.

[0016] Located on a first end 140 of the tubular casing 110 is a primer receiver 150 configured to receive a primer 155. Those skilled in the pertinent art understand that the function of a primer 155 is to detonate the charge loaded within the shotgun shell when the primer 155 is ignited. The first end 140 is constructed with a rim 160 for retaining the tubular casing 110 within the firing chamber of the shotgun of the greater gauge. Located on a second end 170 and distal to the first end 140 is a closure 180 configured to retain a charge 190 (shown in FIG. 2) for the lesser gauge within the tubular casing 110 until the primer 155 is ignited.

[0017] The present invention thus provides a completely loaded shotgun shell that is of a smaller or lesser gauge that the shotgun from which it can be fired. This increases the versatility of a shotgun to a clay target shooter or sportsman-hunter who can now carry and use loaded shotgun shells of a lesser gauge without having to add a mechanical device to the gun that permits the use of a smaller gauge shell in a larger gauge shotgun.

[0018] Turning now to FIG. 2, illustrated is a breakout view of components 200 of the charge 190 loaded in a shotgun shell hull 100 of the type illustrated in FIG. 1. The charge 190 components 200 are gunpowder 220 (herein “powder”), a wad 230 (or multiple wads 235, if a single piece wad is not used), and shot 240. After a primer 155 is located in the first end 140, a predetermined charge of powder 220 is placed in the hull 100. After the charge of powder 220 is loaded, a wad 230 is placed in the hull 100 over the powder 220, followed by predetermined amount of shot 240.

[0019] The wad 230 in the shotgun shell 100 serves many functions. One such function is to maintain pressure on the powder 220 and assure uniform ignition. Another function is to take up the space in the hull 100 not occupied by the shot 240 and powder 220. Other wad 230 functions include protecting the shot 240 from upset when the powder 220 is ignited; provide a barrel seal so that pressure from gases expended by burning powder 220 can efficiently impart velocity to the load of shot 240; and cushion the shot 240 to prevent excessive deformation from pressure caused by the powder 220 gases. In the case of one-piece plastic wads 230 with a built in shot cup 231, the wad 230 also protects the shot 240 from deformation caused by barrel scrub. Although powder 220 and shot 230 are not size specific, this is not the case with wads 230. A twenty gauge wad 230, whether a modern plastic wad 230 or an older fiber or cardboard wad 235, can only be used in a shell 100 having an inside diameter of a twenty gauge shell 100. The same is true with respect to the other gauges.

[0020] A particularly valuable aspect of the one piece plastic wad 230 is that the wad 230 expands to match the inside diameter of the shotgun barrel as soon as the wad 230 leaves the confines of the shotgun shell 100. In most cases this is attributable to a cushion 232 portion of the wad 230 that collapses from the pressure of the gases caused by the burning powder 210. It is this aspect that permits the efficient use of a twenty gauge shotgun shell, constructed in accordance with the present invention, to be used in a twelve gauge shotgun where the shell that has the outside diameter of a twelve gauge shell.

[0021] Turning now to FIG. 3, illustrated are isometric views of embodiments of the present invention showing various closure 300 arrangements for forming a closure 180 at the second end 170 of the shot shell hull 100 illustrated in FIG. 1. In one embodiment, the closure 180 is made by an end crimp 310 where the entire end of the tubular case 110 is folded to close the shell 100 and hold the lesser gauge charge in place. In some cases, however, it may be difficult to form an end crimp 310 because of the thickness of the tubular casing 110. Thus, in one embodiment of the invention an inside diameter crimp 320 is used to form the closure 180. In this embodiment, the tubular casing 110 can be made having a inside portion of the casing 110 extended to a length sufficient to form the closure by crimping. In still another embodiment, on outside diameter crimp 330 can be used where the closure 180 is formed from the outside diameter of the tubular casing 110. In yet another embodiment of the invention the closure 180 used to retain the sub-gauge charge in the hull can be an overshot wad 340. This overshot wad 340 can be held in place by roll-crimping the edge of the tubular casing or it can be secured in place with an adhesive. As those skilled in the pertinent art will understand any kind or type of closure can be used to retain the sub-gauge charge in the hull and be within the intended scope of the present invention.

[0022] Although one embodiment of the invention provides for the shotgun shell hull 100 to utilize a plastic tubular casing 110 and another provides for a tubular casing 110 of paper, the scope of the present invention is not so limited. Any other material, whether now known or subsequently discovered, can be used and still be within the scope of the present invention. Thus a tubular casing 110 of brass or other metallic material will still be within the intended scope of the present invention.

[0023] In one embodiment of the present invention provides for the greater gauge of the shotgun shell hull outer diameter to be selected from the group consisting of a ten gauge; a twelve gauge; a sixteen gauge; a twenty gauge; and a twenty eight gauge. These are the commonly recognized United States shotgun gauges. Nevertheless, there are several other shotgun gauges that will be within the intended scope of the present invention. Thus an eight gauge or a fourteen gauge, can be used as the greater gauge in the present invention. Similarly, in one embodiment of the invention the lesser gauge of the inside diameter of the shotgun shell hull is selected from the group consisting of a twelve gauge; a sixteen gauge; a twenty gauge; a twenty eight gauge, and a 410 gauge. Again these are the gauges commonly recognized in the United States as being within the scope of potential lesser gauges. Again, there are several other shotgun gauges that will be within the intended scope of the present invention, such as a fourteen gauge, a twenty-four gauge or a thirty-six gauge, all of which have been manufactured at one time or another as a recognized shotgun gauge.

[0024] The present invention also includes several methods of manufacturing a shotgun shell hull, all of which will be readily understood by those skilled in the pertinent art based on the foregoing disclosure. In a similar fashion the present invention also includes several methods of using a shotgun shell hull, all of which will be readily understood by those skilled in the pertinent art based on the foregoing disclosure.

[0025] Although the present invention has been described in detail, those skilled in the art should understand that they can make various changes, substitutions and alterations herein without departing from the spirit and scope of the invention in its broadest form. 

What is claimed is:
 1. A shotgun shell hull, comprising: a tubular casing having an outer diameter of about a greater gauge and an inside diameter of about a lesser gauge; a primer receiver located on a first end of said tubular casing, configured to receive a primer and having a rim for retaining said tubular casing within a firing chamber of a shotgun of said greater gauge; and a closure located on a second end of said tubular casing distal to said first end and configured to retain a charge for said lesser gauge in said tubular casing until said primer is ignited.
 2. The shotgun shell hull as recited in claim 1 wherein said closure is a crimp formed from said outer diameter of said tubular casing.
 3. The shotgun shell hull as recited in claim 1 wherein said closure is a crimp formed from said inside diameter of said tubular casing.
 4. The shotgun shell hull as recited in claim 1 wherein said closure is an overshot wad.
 5. The shotgun shell hull as recited in claim 1 wherein said tubular casing is plastic.
 6. The shotgun shell hull as recited in claim 1 wherein said tubular casing is paper.
 7. The shotgun shell hull as recited in claim 1 wherein said greater gauge is selected from the group consisting of: a ten gauge; a twelve gauge; a sixteen gauge; a twenty gauge; and a twenty eight gauge.
 8. The shotgun shell hull as recited in claim 1 wherein said lesser gauge is selected from the group consisting of: a twelve gauge; a sixteen gauge; a twenty gauge; a twenty eight gauge, and a 410 gauge.
 9. A method of manufacturing a shotgun shell hull, comprising: forming a tubular casing having an outer diameter of about a greater gauge and an inside diameter of about a lesser gauge; forming a first end of said tubular casing having a primer receiver located thereon configured to receive a primer and having a rim for retaining said tubular casing within a firing chamber of a shotgun of said greater gauge; and forming a closure on a second end of said tubular casing distal to said first end and configured to retain a charge for said lesser gauge in said tubular casing until said primer is ignited.
 10. The method of manufacturing as recited in claim 9 wherein said closure is a crimp formed from said outer diameter of said tubular casing.
 11. The method of manufacturing as recited in claim 9 wherein said closure is a crimp formed from said inside diameter of said tubular casing.
 12. The method of manufacturing as recited in claim 9 wherein said closure is an overshot wad.
 13. The method of manufacturing as recited in claim 9 wherein said tubular casing is plastic.
 14. The method of manufacturing as recited in claim 9 wherein said tubular casing is paper.
 15. The method of manufacturing as recited in claim 9 wherein said greater gauge is selected from the group consisting of: a ten gauge; a twelve gauge; a sixteen gauge; a twenty gauge; and a twenty eight gauge.
 16. The method of manufacturing as recited in claim 9 wherein said lesser gauge is selected from the group consisting of: a twelve gauge; a sixteen gauge; a twenty gauge; a twenty eight gauge, and a 410 gauge.
 17. A method of using a shotgun shell hull, comprising: selecting a shotgun shell, said shotgun shell having; a tubular casing having an outer diameter of about a greater gauge and an inside diameter of about a lesser gauge; a primer receiver located on a first end of said tubular casing, configured to receive a primer and having a rim for retaining said tubular casing within a firing chamber of a shotgun of said greater gauge; and a closure located on a second end of said tubular casing distal to said first end and configured to retain a charge for said lesser gauge in said tubular casing until said primer is ignited; and loading said shotgun shell into a shotgun.
 18. The method of using a shotgun shell hull as recited in claim 17 wherein said closure is selected from the group consisting of: a crimp formed from said outer diameter of said tubular casing; a crimp formed from said inside diameter of said tubular casing; and an overshot wad.
 19. The method of using a shotgun shell hull as recited in claim 17 wherein said greater gauge is selected from the group consisting of: a ten gauge; a twelve gauge; a sixteen gauge; a twenty gauge; and a twenty eight gauge.
 20. The method of using a shotgun shell hull as recited in claim 17 wherein said lesser gauge is selected from the group consisting of: a twelve gauge; a sixteen gauge; a twenty gauge; a twenty eight gauge, and a 410 gauge. 